Contents: System discharge ⤓ Small system discharge ⤓ Pipelines and connections ⤓ Checking the noise level of the air…⤓ Adjustment ⤓
System discharge
If the system has lost all refrigerant due to a leak, follow the steps below.
Empty the system.
Fill the system with refrigerant: approximately 480 to 520 g.
Check for leaks.
Empty the system.
Fix the leaks.
Attention! Replacement of the filter-dryer unit is carried out with the air conditioner not working. The dehydrator used in these units quickly becomes saturated with water from the air atmosphere. When installing the dehydrator, prepare all the necessary tools and materials for its quick replacement in order to keep the system open to the air as little as possible.
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Replace the receiver drier.
Empty and refill the system.
Small system discharge
If the system has not lost all of its refrigerant charge, locate and repair refrigerant leaks. If necessary, pressurize the system to make it easier to locate leaks by adding refrigerant. If possible, repair the refrigerant leak without draining the system; in this case, use the appropriate method when recharging the system.
Pipelines and connections
Kinks in the pipes or sharp bends in the air conditioning system hoses dramatically reduce the efficiency of the system. In this case, the pressure in the system elements increases sharply when the air conditioner is running. Particular attention must be paid to the reliability of fastening all connections of the system. Dirt and moisture can get into the system during its repair during the replacement of lines or system elements. The following precautions must be taken into account. Before disconnecting any fittings of the air conditioning system, the system must be completely drained. Even with a completely drained system, disconnecting the system fittings must be done with extreme caution. If residual pressure is noticed in the system when disconnecting fittings, the pressure must be released very slowly.
Changing the shape of the pipes by re-bending them is not allowed. It is allowed to use pipes of the original bend during their installation. For flexible hoses, a rule of the maximum bending radius is established: it must be at least 10 hose diameters. A smaller bending radius reduces the fluidity of the refrigerant. Flexible hoses of the air conditioning system should not be closer than 80 mm from the exhaust manifold of the engine. A good rule is considered to be an annual inspection of the flexible hoses of the system: their condition and the condition of the seals.
If there are seals such as O-rings: their reuse is not permitted.
Checking the noise level of the air conditioner
It is necessary to know the reasons for the appearance of extraneous noise during compressor operation. These reasons may be: weather, vehicle speed, movement in gear or coasting, engine thermal condition and other reasons.
The noise that occurs when the air conditioner is running can sometimes be misleading. For example: the noise of a worn bearing or a loose connecting rod can be caused by loose bolts, nuts, mounting brackets, or a worn electromagnetic clutch. Check the tension of the drive belts (power steering, alternator). Incorrect tension of the drive belts can cause a distracting noise when the compressor is turned on and a decrease or absence of noise when the compressor is turned off. Drive belts are very sensitive to speed. At different engine speeds and depending on the belt tension, the belts can make a noise that can easily be confused with noise from mechanical failure of the compressor.
Adjustment
Select a quiet area to perform the test. Repeat the same test situation many times. Turn the air conditioner on and off several times to clearly identify the noise produced by the air conditioner. To simulate severe environmental conditions (high pressure), limit the air flow through the condenser. Install a measuring manifold to create a pressure at the outlet not exceeding 2070 kPa.
Tighten all compressor mounting bolts, clutch mounting bolts, tighten the compressor drive belt. Check the condition of the compressor electromagnetic clutch winding (no turning or mobility).
Check the condition of the air conditioning hoses for any rubbing or tangling, which may cause additional noise.
Check the refrigerant charge.
Check again for noise from step 1.
If the noise persists, loosen the compressor mounting bolts and retighten them. Repeat step 1.
If the noise still persists, replace the compressor and repeat the test from step 1.